1. Field of the Invention
The present invention relates to a tool for taking fluid samples from a specific location in a pressurized vessel or a pipeline and for unplugging or removal of blockage from piping vents and drain valves.
2. Description of the Prior Art
It is frequently necessary or desirable to take samples of fluid, gas or liquid stored in pressurized vessels or flowing through a pipeline. The fluid samples are often taken from a vessel or a pipeline to obtain necessary information relating to the fluid's condition, composition and the like, e.g., fluid samples are often taken for chemical analysis. It is also desirable to be able to extract fluid samples from a specific location in the vessel or pipeline. It is further desirable to have an improved tool capable of unplugging blocked drains, vent valves, etc. It is particularly important to have such a tool in the oil industry for unplugging drains and the like without leaking of a hydrocarbon product that is contained in a vessel or flows through the pipeline, and without release of dangerous gases.
All industrial plants face a problem of removal of fluid samples because of the sample valve location for a particular pipe. Therefore, there is a need for a sampling and blockage removal tool that would permit taking samples from a desired location and in the oil industry, in particular, would prevent the danger of a sudden release of hydrocarbons in case of sludge blocking and, generally, would prevent any industrial leakage and emission of hydrocarbons or other hazardous chemicals. In this regard, the tool packing should provide reliable sealing performance.
The prior art discloses a number of different tools and apparatus for taking samples and/or inserting objects in a pipeline. Some examples follow.
U.S. Pat. No. 3,831,452 discloses a sampling device for retrieving a sample of gas in a pipeline or any desired area therein. The sampling device is securable on a ball valve mounted at a sampling port of a pipe. The device includes a housing having a sampling tube fixedly secured therein. The housing is fixedly secured to a wheel for joint displacement therewith. The wheel hub is provided with an inner thread that cooperates with a hollow threaded stem for displacing the housing together with the sampling tube along the threaded stem. The stem is provided with a threaded fitting for securing the stem in the ball valve. The sampling tube has a packing gland mounted thereon. At its end projecting from the housing, the sampling tube is provided with a thread for cooperation with a suitable valve that controls the flow of fluid through the sampling pipe.
The device has too many parts and is rather complex. Moreover, with the wheel secured to the housing, the entire structure should be displaced for advancing the sampling tube.
U.S. Pat. No. 4,120,313 discloses an apparatus for insertion of a corrosion coupon in a pipeline and removing it therefrom. The apparatus is mounted on a ball valve. The apparatus includes a cylinder and an elongate rack which is guided with the cylinder by a guide secured in the cylinder. A corrosion coupon is mounted at the operating end of the rack which is displaced by a pinion secured on the shaft attached to a handwheel. The device of the U.S. Pat. No. 4,120,313 is also very complex. Use of plurality of stems adds to the complexity of the device and a potential fluid release.
U.S. Pat. No. 4,294,124 discloses an apparatus for extraction of materials from operating vessels and including a ball valve securable to a ball valve fixedly secured at the extraction port, and an outer tube securable to the valve. An inner tube is longitudinally displaceable in the outer tube and has at its end perforations for extracting particles. A threaded rod extends into the inner tube through a threaded bore at the end of the tube remote from the ball valve. The rod is connected to a crank. The inner tube is displaceable along the rod upon rotation of the crank due to cooperation of the threaded rod with the threaded bore of tube. As in '313 patent, a plurality of stem elements add to the complexity of the device.
U.S. Pat. No. 6,860,162 discloses a device for extracting liquid fluid samples—mainly wine. The device includes a tubular probe that extends through the device body and a cylindrical plunger extending through a passage formed in the probe. The plunger moves between a first position in which the plunger tip is moved out of the passage inlet, and a second position when the passage inlet is closed. The construction of the wine sampler and, in particular the mechanism for displacing the plunger is rather complex.
A common drawback of the above-described prior art devices and methods is a comparatively complex arrangement for advancing the sampling tube. Furthermore, the known devices, because of their complexity, cannot always take a sample from a desired predetermined location.
Accordingly, an object of the present invention is to provide a sampling and blockage removal tool that solves the problem of taking a fluid sample at any predetermined location safely and reliably, while preventing any release of hazardous material into the environment.